The bis-biguanide compound, chlorhexidine, particularly in the form of its salts, is a known antimicrobial compound.
Liquid skin cleansing compositions containing chlorhexidine and its salts are also known in the prior art, as, for example, in U.S. Pat. Nos. 4,456,543, Owens, issued June 26, 1984, and 4,326,977, Schmolka, issued Apr. 27, 1982. Both of these patents are directed to liquid compositions which utilize certain nonionic surfactants in combination with chlorhexidine, preferably in the form of its high solubility gluconate salt. These patents teach that anionic surfactant destroy or greatly decrease the antimicrobial efficacy of the chlorhexidine compounds.
Senior, J. Soc. Cosmet. Chem., 24, pp. 259-278 (1973) teaches that excess of stearate soap completely inactivates chlorhexidine, although slight activity is detectable for the salt, chlorhexidine stearate.
Block, Disinfection, Sanitization+Preservation, Lea & Febiger, Philadelphia (1983), at p. 252, teaches that soaps are incompatible with chlorhexidine, but that aqueous or alcoholic chlorhexidine can be applied to the skin after washing the skin with soap and water, provided that rinsing is interposed to remove the lather before applying chlorhexidine.